"They likely follow prey in. Over the past two days, DOC received reports of this dolphin swimming through the inlet on its own.

"Rangers in the area weren't able to spot it and we generally don't intervene unless there are signs of serious injury.

The dolphin was a common dolphin, just over two metres in length.

"It is not an uncommon occurrence in New Zealand to have marine mammals wash up on our shore either alive or dead. We are a hotspot for marine mammals, we get around 85 strandings per year, a mixture of live and dead animals," Mace said.

The discovery was called in by a member of the public on Friday morning on his way to work.

"Once we got this morning's call, the team acted swiftly to notify iwi and shift the dolphin."